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                        多线程
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                            <b>0.1.</b>
                        
                        多线程
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                            <b>0.2.</b>
                        
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                            <b>0.3.</b>
                        
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                            <b>0.3.1.</b>
                        
                        创建线程的方式
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                            <b>0.3.2.</b>
                        
                        NSThread 的 Target
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                            <b>0.3.3.</b>
                        
                        线程状态
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                            <b>0.3.4.</b>
                        
                        线程属性
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                            <b>0.3.5.</b>
                        
                        资源共享
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                            <b>0.3.6.</b>
                        
                        原子属性
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                            <b>0.3.7.</b>
                        
                        线程间通讯
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                            <b>0.4.</b>
                        
                        GCD
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                            <b>0.4.1.</b>
                        
                        同步 &amp; 异步
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                            <b>0.4.2.</b>
                        
                        block
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                            <b>0.4.3.</b>
                        
                        GCD 常用代码
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                            <b>0.4.4.</b>
                        
                        串行队列
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                            <b>0.4.5.</b>
                        
                        并发队列
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                            <b>0.4.6.</b>
                        
                        主队列
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                            <b>0.4.7.</b>
                        
                        同步任务的作用
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                            <b>0.4.8.</b>
                        
                        Barrier 异步
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                            <b>0.4.9.</b>
                        
                        全局队列
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                            <b>0.4.10.</b>
                        
                        延迟操作
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                            <b>0.4.11.</b>
                        
                        一次性执行
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                            <b>0.4.12.</b>
                        
                        调度组
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                            <b>0.5.</b>
                        
                        NSOperation
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                            <b>0.5.1.</b>
                        
                        基本演练
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                            <b>0.5.2.</b>
                        
                        高级演练
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                            <b>0.5.3.</b>
                        
                        与 GCD 的对比
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                            <b>0.5.4.</b>
                        
                        自定义操作
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                            <b>0.6.</b>
                        
                        异步加载图片
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                            <b>0.6.1.</b>
                        
                        搭建界面&amp;数据准备
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                            <b>0.6.2.</b>
                        
                        同步加载图像
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                            <b>0.6.3.</b>
                        
                        异步加载图像
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                            <b>0.6.4.</b>
                        
                        占位图像
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                            <b>0.6.5.</b>
                        
                        MVC
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                            <b>0.6.6.</b>
                        
                        操作缓冲池
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                            <b>0.6.7.</b>
                        
                        图像缓冲池
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                            <b>0.6.8.</b>
                        
                        代码重构
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                            <b>0.6.9.</b>
                        
                        内存警告
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                            <b>0.6.10.</b>
                        
                        黑名单
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                            <b>0.6.11.</b>
                        
                        沙盒缓存
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                            <b>0.6.12.</b>
                        
                        小结
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                            <b>0.6.13.</b>
                        
                        SDWebImage初体验
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                            <b>0.7.</b>
                        
                        仿SDWebImage
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                            <b>0.7.1.</b>
                        
                        下载操作
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                            <b>0.7.2.</b>
                        
                        测试下载操作
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                            <b>0.7.3.</b>
                        
                        下载管理器
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                            <b>0.7.4.</b>
                        
                        自定义 UIImageView
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                            <b>0.8.</b>
                        
                        SDWebImage
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                            <b>0.8.1.</b>
                        
                        第三方框架
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                            <b>0.8.2.</b>
                        
                        位移枚举
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                            <b>0.8.3.</b>
                        
                        NSCache
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                            <b>0.8.4.</b>
                        
                        SDWebImage常见面试题
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                            <b>0.9.</b>
                        
                        runloop
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                            <b>0.10.</b>
                        
                        自动释放池
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        <a href="./" >多线程</a>
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                        <h1 id="%E5%8D%A0%E4%BD%8D%E5%9B%BE%E5%83%8F">&#x5360;&#x4F4D;&#x56FE;&#x50CF;</h1>
<pre><code class="lang-objc"><span class="hljs-comment">// 0. &#x5360;&#x4F4D;&#x56FE;&#x50CF;</span>
<span class="hljs-built_in">UIImage</span> *placeholder = [<span class="hljs-built_in">UIImage</span> imageNamed:<span class="hljs-string">@&quot;user_default&quot;</span>];
cell<span class="hljs-variable">.imageView</span><span class="hljs-variable">.image</span> = placeholder;
</code></pre>
<h2 id="%E9%97%AE%E9%A2%98">&#x95EE;&#x9898;</h2>
<ul>
<li>&#x56E0;&#x4E3A;&#x4F7F;&#x7528;&#x7684;&#x662F;&#x7CFB;&#x7EDF;&#x63D0;&#x4F9B;&#x7684; cell</li>
<li>&#x6BCF;&#x6B21;&#x548C; cell &#x4EA4;&#x4E92;&#xFF0C;<code>layoutSubviews</code> &#x65B9;&#x6CD5;&#x4F1A;&#x6839;&#x636E;&#x56FE;&#x50CF;&#x7684;&#x5927;&#x5C0F;&#x81EA;&#x52A8;&#x8C03;&#x6574; <code>imageView</code> &#x7684;&#x5C3A;&#x5BF8;</li>
</ul>
<h2 id="%E8%A7%A3%E5%86%B3%E5%8A%9E%E6%B3%95">&#x89E3;&#x51B3;&#x529E;&#x6CD5;</h2>
<ul>
<li>&#x81EA;&#x5B9A;&#x4E49; Cell</li>
</ul>
<h1 id="%E8%87%AA%E5%AE%9A%E4%B9%89-cell">&#x81EA;&#x5B9A;&#x4E49; Cell</h1>
<pre><code class="lang-objc">cell<span class="hljs-variable">.nameLabel</span><span class="hljs-variable">.text</span> = app<span class="hljs-variable">.name</span>;
cell<span class="hljs-variable">.downloadLabel</span><span class="hljs-variable">.text</span> = app<span class="hljs-variable">.download</span>;

<span class="hljs-comment">// &#x5F02;&#x6B65;&#x52A0;&#x8F7D;&#x56FE;&#x50CF;</span>
<span class="hljs-comment">// 0. &#x5360;&#x4F4D;&#x56FE;&#x50CF;</span>
<span class="hljs-built_in">UIImage</span> *placeholder = [<span class="hljs-built_in">UIImage</span> imageNamed:<span class="hljs-string">@&quot;user_default&quot;</span>];
cell<span class="hljs-variable">.iconView</span><span class="hljs-variable">.image</span> = placeholder;

<span class="hljs-comment">// 1. &#x5B9A;&#x4E49;&#x4E0B;&#x8F7D;&#x64CD;&#x4F5C;</span>
NSBlockOperation *downloadOp = [NSBlockOperation blockOperationWithBlock:^{
    <span class="hljs-comment">// 1. &#x6A21;&#x62DF;&#x5EF6;&#x65F6;</span>
    <span class="hljs-built_in">NSLog</span>(<span class="hljs-string">@&quot;&#x6B63;&#x5728;&#x4E0B;&#x8F7D; %@&quot;</span>, app<span class="hljs-variable">.name</span>);
    [<span class="hljs-built_in">NSThread</span> sleepForTimeInterval:<span class="hljs-number">0.5</span>];
    <span class="hljs-comment">// 2. &#x5F02;&#x6B65;&#x52A0;&#x8F7D;&#x7F51;&#x7EDC;&#x56FE;&#x7247;</span>
    <span class="hljs-built_in">NSURL</span> *url = [<span class="hljs-built_in">NSURL</span> URLWithString:app<span class="hljs-variable">.icon</span>];
    <span class="hljs-built_in">NSData</span> *data = [<span class="hljs-built_in">NSData</span> dataWithContentsOfURL:url];
    <span class="hljs-built_in">UIImage</span> *image = [<span class="hljs-built_in">UIImage</span> imageWithData:data];

    <span class="hljs-comment">// 3. &#x4E3B;&#x7EBF;&#x7A0B;&#x66F4;&#x65B0; UI</span>
    [[NSOperationQueue mainQueue] addOperationWithBlock:^{
        cell<span class="hljs-variable">.iconView</span><span class="hljs-variable">.image</span> = image;
    }];
}];

<span class="hljs-comment">// 2. &#x5C06;&#x4E0B;&#x8F7D;&#x64CD;&#x4F5C;&#x6DFB;&#x52A0;&#x5230;&#x961F;&#x5217;</span>
[<span class="hljs-keyword">self</span><span class="hljs-variable">.downloadQueue</span> addOperation:downloadOp];
</code></pre>
<h2 id="%E9%97%AE%E9%A2%98">&#x95EE;&#x9898;</h2>
<ul>
<li><p>&#x5982;&#x679C;&#x7F51;&#x7EDC;&#x56FE;&#x7247;&#x4E0B;&#x8F7D;&#x901F;&#x5EA6;&#x4E0D;&#x4E00;&#x81F4;&#xFF0C;&#x540C;&#x65F6;&#x7528;&#x6237;&#x6EDA;&#x52A8;&#x56FE;&#x7247;&#xFF0C;&#x53EF;&#x80FD;&#x4F1A;&#x51FA;&#x73B0;&#x56FE;&#x7247;&#x663E;&#x793A;&quot;&#x9519;&#x884C;&quot;&#x7684;&#x95EE;&#x9898;</p>
</li>
<li><p>&#x4FEE;&#x6539;&#x5EF6;&#x65F6;&#x4EE3;&#x7801;&#xFF0C;&#x67E5;&#x770B;&#x9519;&#x8BEF;</p>
</li>
</ul>
<pre><code class="lang-objc"><span class="hljs-comment">// 1. &#x6A21;&#x62DF;&#x5EF6;&#x65F6;</span>
<span class="hljs-keyword">if</span> (indexPath<span class="hljs-variable">.row</span> &gt; <span class="hljs-number">9</span>) {
    [<span class="hljs-built_in">NSThread</span> sleepForTimeInterval:<span class="hljs-number">3.0</span>];
}
</code></pre>
<p>&#x4E0A;&#x4E0B;&#x6EDA;&#x52A8;&#x4E00;&#x4E0B;&#x8868;&#x683C;&#x5373;&#x53EF;&#x770B;&#x5230; cell &#x590D;&#x7528;&#x7684;&#x9519;&#x8BEF;</p>
<h2 id="%E8%A7%A3%E5%86%B3%E5%8A%9E%E6%B3%95">&#x89E3;&#x51B3;&#x529E;&#x6CD5;</h2>
<ul>
<li>MVC</li>
</ul>

                    
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